TABLE 4

Genetic contents and antibiotic susceptibilities of A. baumannii sulbactam-resistant mutants

StrainConcn at which mutant was isolatedMutationMIC (μg/ml)a
SULATMCAZMEMCIPCST
ATCC 17978
    Wild-typeNANA116160.250.250.25
    4-24× MICPBP3 (S390T)643280.1250.250.25
ARC2058
    Wild-typeNANA13280.250.250.5
    2-162× MICGalE (E192K)43280.0.50.0.52
    4-24× MICPBP3 (S395F)b323280.50.50.5
    4-284× MICl,d-Transpeptidasec43280.250.251
    4-294× MICMraY (T23I)832160.50.51
    8-188× MICRpoC (R803H)8128640.50.50.5
  • a SUL, sulbactam; ATM, aztreonam; CAZ, ceftazidime; MEM, meropenem; CIP, ciprofloxacin; CST, colistin; NA, not applicable.

  • b Also contains a frameshift mutation in a peptidase C13 family protein at Gly50.

  • c L20fs:Δ82 bp.